Transpyloric Feed in Reflux-Associated Apnea in Preterm Newborns: A Prospective Study.

Background: The etiological correlation between gastroesophageal reflux (GER) and apnea is controversial. We conducted a prospective interventional study designed to address the controversy. Methods: Preterm neonates with apnea at a tertiary care center, who had clinical features of GER without any other comorbidities likely to cause apnea, were included in the study. The enrolled neonates underwent continuous transpyloric tube feeding for 72 hours. The primary outcome measure was the difference in the number of apneic episodes pre- and post-initiation of nasoduodenal (ND) feeding. Secondary outcome measures included the incidence of necrotizing enterocolitis, other gastrointestinal disturbances, and mortality. Results: Sixteen preterm neonates were included in the study. A substantial proportion (n =11, 68.8%) of the included neonates had a reduction in the number of apneic episodes. There was a significant decrease in the mean number of apneic episodes from 1.75 (±0.837) to 0.969 (±0.957) (P=.007). The median number of apneas was 1.5 (IQR 0.875) before and 0.5 (IQR 0.875) after ND feeds. There were no serious adverse events observed that were attributable to transpyloric feeding. Conclusion: This prospective study suggests that in a selected group of preterm neonates with reflux- associated apnea, transpyloric feeding can be an effective therapeutic modality.

Framework structured Ce2(C2O4)3·10H2O as a pseudocapacitive electrode of a hybrid (asymmetric) supercapacitor (HSC) for large scale energy storage applications.

The electrochemical kinetics of the electrode material plays a crucial role in the development of various energy storage devices such as batteries, supercapacitors, and hybrid supercapacitors. Battery-type hybrid supercapacitors are envisaged as excellent candidates to bridge the performance gap between supercapacitors and batteries. Due to its open pore framework structure and more structural stability, porous cerium oxalate decahydrate (Ce2(C2O4)3·10H2O) is found here to be a potential energy storage material partly because of the presence of planer oxalate anions (C2O42-). Superior specific capacitance equivalent to 78 mA h g-1 (capacitance: 401 F g-1) at 1 A g-1 in the potential window of -0.3 to 0.5 V was observed in an aqueous 2 M KOH electrolyte. The predominant pseudocapacitance mechanism seems to operate because of the high charge storage capacity of the electrode as intercalative (diffusion control) and surface control charges stored by the porous anhydrous Ce2(C2O4)3·10H2O, which were close to 48% and 52%, respectively, at a 10 mV s-1 scan rate. Further, in the full cell asymmetric supercapacitor (ASC) mode in which porous Ce2(C2O4)3·10H2O is the positive electrode and activated carbon (AC) is the negative electrode, at the operating potential window of 1.5 V, the highest specific energy of 96.5 W h kg-1 and a specific power of ∼750 W kg-1 at 1 A g-1 current rate and a high power density of 1453 W kg-1, the hybrid supercapacitor still attains an energy density of 10.58 W h kg-1 at a 10 A g-1 current rate, which was obtained with a high cyclic stability. The detailed electrochemical studies confirm a high cyclic stability and a superior electrochemical charge storage property of porous Ce2(C2O4)3·10H2O making it a potential pseudocapacitive electrode for use in large energy storage applications.

Zn(II)-Catalyzed Selective N-Alkylation of Amines with Alcohols Using Redox Noninnocent Azo-Aromatic Ligand as Electron and Hydrogen Reservoir.

We report a sustainable and eco-friendly approach for selective N-alkylation of various amines by alcohols, catalyzed by a well-defined Zn(II)-catalyst, Zn(La)Cl2 (1a), bearing a tridentate arylazo scaffold. A total of 57 N-alkylated amines were prepared in good to excellent yields, out of which 17 examples are new. The Zn(II)-catalyst shows wide functional group tolerance, is compatible with the synthesis of dialkylated amines via double N-alkylation of diamines, and produces the precursors in high yields for the marketed drugs tripelennamine and thonzonium bromide in gram-scale reactions. Control reactions and DFT studies indicate that electron transfer events occur at the azo-chromophore throughout the catalytic process, which shuttles between neutral azo, one-electron reduced azo-anion radical, and two-electron reduced hydrazo forms acting both as electron and hydrogen reservoir, enabling the Zn(II)-catalyst for N-alkylation reaction.

Nanocrystalline ß-NiS: a redox-mediated electrode in aqueous electrolyte for pseudocapacitor/supercapacitor applications.

Currently, enhancing the performance of electrochemical supercapacitors is the subject of intense research to fulfill the ever-increasing demand for grid-scale energy storage and delivery solution, thereby utilizing the full potential of renewable energy resources and decreasing our dependence on fossil fuels. Metal sulfides, such as cobalt sulfide (CoS), nickel sulfide (NiS), molybdenum sulfide (MoS), copper sulfide (CuS), and others, have recently emerged as a promising class of active electrode materials, alongside other supercapacitor electrode materials, due to their relatively high specific capacitance values and exceptional reversible redox reaction activities. The synthesis, characterizations, and electrochemical performances of single-phase nanocrystalline ß-NiS are presented here and the electrode based on this material shows a specific capacitance of 1578 F g-1 at 1 A g-1 from the galvanostatic discharge profile, whereas a capacitance of 1611 F g-1 at 1 mV s-1 was obtained through the CV curve in 2 M KOH aqueous electrolyte. Additionally, the electrode also performs well in neutral 0.5 M Na2SO4 electrolytes resulting in specific capacitance equivalent to 403 F g-1 at 1 mV s-1 scan rate. The high charge storage capacity of the material is due to the superior intercalative (inner) charge storage coupled with the surface (outer) charges stored by the ß-NiS electrode and was found to be 72% and 28%, respectively, in aqueous 2 M KOH electrolyte. This intercalative charge storage mechanism is also responsible for its excellent cycling stability. Additionally, we assembled aqueous asymmetric supercapacitors (ASCs) with activated carbon (AC) as the negative electrode and the ß-NiS electrode as the positive electrode. The combination of the ß-NiS electrode and AC with excellent cycling stability resulted in the highest specific energy equivalent to ∼163 W h kg-1 and a specific power of ∼507 W kg-1 at 1 A g-1 current rate.

Effect of strontium doping on the electrochemical pseudocapacitance of Y1-xSrxMnO3-δ perovskites.

Grid-scale bulk energy storage solutions are needed to utilize the full potential of renewable energy technologies. Pseudocapacitive electrochemical energy storage can play a vital role in developing efficient energy storage solutions. The use of perovskites as anion intercalation-type pseudocapacitor electrodes has received significant attention in recent years. In this study, Sr-doped YMnO3i.e. Y1-xSrxMnO3-δ perovskite was prepared by the solid-state ceramic route and studied for electrochemical pseudocapacitance in aqueous KOH electrolyte. Microstructures, morphologies, and electrochemical properties of these materials were investigated through X-ray diffraction (XRD), scanning electron microscopy (SEM), cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrochemical impedance method. The formation of the mostly cubic phase, with 50% strontium doped YMnO3 (YSMO-50) provides an equivalent three-dimensional network and superior conductivity due to Mn3+-O2--Mn4+ hopping conduction. YSMO-50 exhibited low intrinsic resistance, 1.45 Ω cm-2, and the highest specific capacity, 259.83 F g-1 at a current density of 1 A g-1 in 2 M KOH aqueous electrolyte. Redox-mediated interconversion of oxide to hydroxide (M2+O2- + H2O + e- ↔ M+OH- + OH-) in aqueous media is shown to be the reason behind the high capacitance of YSMO-50. The excellent electrochemical performance of YSMOs was attributed to the reversible interconversion of oxide-ion into hydroxide ion coupled with surface redox reaction of Mn2+/Mn3+ and Mn3+/Mn4+ occurring during the charge-discharge process. The maximum energy density of 65.13 W h kg-1 was achieved at a power density of 0.45 kW kg-1 for an asymmetric mode, in which YSMO serves as a negative electrode and Activated carbon (AC) as a positive electrode in the PVA-KOH gel electrolyte. Our study reveals that the doping of low valence atom (Sr) at the A-site in perovskite manganites (YMnO3) may be an effective tool to enhance the pseudocapacitive performance of perovskite-based electrodes.

Perovskite La1-xKxCoO3-δ (0 ≤ x ≤ 0.5): a novel bifunctional OER/ORR electrocatalyst and supercapacitive charge storage electrode in a neutral Na2SO4 electrolyte.

The as-prepared La1-xKxCoO3-δ (0 ≤ x ≤ 0.5) showed superior pseudocapacitive charge storage capacity in a neutral 0.5 M Na2SO4 electrolyte and superior electrocatalytic activities for the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) in a 1 M KOH electrolyte. 30% K doped p-type La0.7K0.3CoO3-δ presents superior OER activity with an overpotential of ∼335 mV at 10 mA cm-2 current rate in a 1 M KOH electrolyte. Additionally, La1-xKxCoO3-δ (0 ≤ x ≤ 0.5) presents an excellent charge-storage capacitance in a neutral 0.5 M Na2SO4 electrolyte resulting in a gravimetric capacitance of the La0.5K0.5CoO3-δ electrode equivalent to 378 F g-1, 282 F g-1, 221 F g-1, 163 F g-1, and 74 F g-1 at a current density of 1 A g-1, 2 A g-1, 3 A g-1, 5 A g-1, and 10 A g-1, respectively. After 2500 continuous cycles of charge/discharge, the La0.5K0.5CoO3-δ//AC cell exhibits higher stability, capacitive retention (94%) and coulombic efficiency (97%). The gravimetric charge storage capacity of ASCs (La0.5K0.5CoO3-δ//AC) in the full cell mode showed capacitance equivalent to 308 F g-1, 287 F g-1, 238 F g-1, 209 F g-1 and 162 F g-1 at current densities of 1 A g-1, 2 A g-1, 3 A g-1, 5 A g-1 and 10 A g-1 in a neutral 0.5 M Na2SO4 electrolyte respectively. Maximum specific power equivalent to ∼6884 W kg-1 was observed at a current density of 10 A g-1 when the specific energy reached ∼57 W h kg-1 for the full cell. The double exchange mechanism coupled with stoichiometric oxygen defects present in the perovskite lattice seems to be operative behind the enhanced electrocatalytic OER properties, and additionally, it improves the charge storage kinetics of the La1-xKxCoO3-δ (0 ≤ x ≤ 0.5) electrode in a neutral Na2SO4 electrolyte for supercapacitor application. This work presents a rational strategy for introducing facile oxygen ion defects into perovskite structured La1-xKxCoO3-δ (0 ≤ x ≤ 0.5) to develop multifunctional electrode materials for a supercapacitor and energy conversion (OER/ORR) electrode of metal-air batteries.

A Singlet-Diradical Co(III)-Dimer as a Nonvolatile Resistive Switching Device: Synthesis, Redox-Induced Interconversion, and Current-Voltage Characteristics.

Herein we report a ligand-centered redox-controlled strategy for the synthesis of an unusual binuclear diradical cobalt(III) complex, [Co2III(L•3-)2] (1), featuring two three-electron reduced trianionic monoradical 2,9-bis(phenyldiazo)-1,10-phenanthroline ligands (L•3-) and two intermediate-spin cobalt(III) centers having a Co-Co bond. Controlled ligand-centered oxidation of 1 afforded two mononuclear complexes, [CoII(L•-)(L0)]+ ([3])+ and [CoII(L0)2]2+ ([2]2+), which upon further ligand-centered reduction yielded a di-azo-anion diradical complex, [CoII(L•-)2] (4). In complex 1, two three-electron reduced di-azo-anion monoradical ligands (L•3-) bridge two intermediate Co(III) centers at a distance of 2.387(2) Å, while upon oxidation, one of the coordinating azo-arms of L becomes pendent, and in complexes [2]2+, [3]+, and 4, two tetradentate ligands coordinate a single Co(II) center in a tridentate meridional fashion with one uncoordinated azo-arm from each of the ligands. In the presence of reducing agents, the monomers [2]2+, [3]+, and 4 undergo ligand-centered reduction to form azo-anion radicals, and the otherwise pendent azo-arms in the presence of cobalt(II)-salts like Co(ClO4)2 or CoCl2 bind the second Co(II)-ion; further internal electron transfer from the cobalt center to the arylazo backbone produces the binuclear complex 1. Spectroscopic analysis, DFT studies, and control experiments were performed to understand the electronic structures and the ligand-centered redox-controlled interconversion. The application of complex 1 as a molecular memory device (memristor) was also explored. Complex 1 showed encouraging results as a memristor with a current ON/OFF ratio > 104 and is highly promising for resistive RAM/ROM applications.

Eldfellite-structured NaCr(SO4)2: a potential anode for rechargeable Na-ion and Li-ion batteries.

Recent global concerns over continuously increasing air pollution and the related health risks due to automobile exhaust have shifted our attention towards green transportation. Recent decades have witnessed a revolution in portable energy-storage systems, mainly lithium-based energy-storage devices. However, the uneven distribution of global lithium reserves and its scarcity lead to huge price differences and geopolitical imbalances, and hence the research in energy-storage materials has shifted towards the development of cost-effective, abundant electrode materials. Here, NaCr(SO4)2, a transition metal-based polyanionic layered material with low cost and high stability during the charge/discharge process vs. Na, operating on the basis of the Cr3+/2+ redox couple, is presented. The test materials were characterized by techniques like XRD, FTIR, SEM, UV, XPS, TGA-DTA, and a detailed electrochemical analysis of the charge/discharge capacity of the materials is presented here. Here, the findings provide insights towards achieving a Cr3+/Cr2+ redox-couple-based sodium-ion battery with a specific capacity of 75 mA h g-1 and 150 mA h g-1 at operating voltages of 0.95 V vs. Na and 1.05 V vs. Li, respectively, with 100% coulombic efficiency. Cr2+ is a very special oxidation of Cr that cannot be obtained easily and CrTa2O6 is the only known oxide where Cr exists in the 2+ state. Here, a shift in the redox energy of the Cr3+/2+ couple was obtained due to its bonding with (SO4)2- polyanions in eldfellite that made the accessibility of Cr3+/2+ possible, resulting in the superior intercalation/deintercalation of Na and Li and the superior energy-storage capacity of the NaCr(SO4)2vs. Na/Li cell.

Ruthenium-Catalyzed Dehydrogenative Functionalization of Alcohols to Pyrroles: A Comparison between Metal-Ligand Cooperative and Non-cooperative Approaches.

Herein, we report the synthesis and characterization of two ruthenium-based pincer-type catalysts, [1]X (X = Cl, PF6) and 2, containing two different tridentate pincer ligands, 2-pyrazolyl-(1,10-phenanthroline) (L1) and 2-arylazo-(1,10-phenanthroline) (L2a/2b, L2a = 2-(phenyldiazenyl)-1,10-phenanthroline; L2b = 2-((4-chlorophenyl)diazenyl)-1,10-phenanthroline), and their application in the synthesis of substituted pyrroles via dehydrogenative alcohol functionalization reactions. In catalyst [1]X (X = Cl, PF6), the tridentate scaffold 2-pyrazolyl-(1,10-phenanthroline) (L1) is apparently redox innocent, and all the redox events occur at the metal center, and the coordinated ligands remain as spectators. In contrast, in catalysts 2a and 2b, the coordinated azo-aromatic scaffolds are highly redox-active and known to participate actively during the dehydrogenation of alcohols. A comparison between the catalytic activities of these two catalysts was made, starting from the simple dehydrogenation of alcohols to further dehydrogenative functionalization of alcohols to various substituted pyrroles to understand the advantages/disadvantages of the metal-ligand cooperative approach. Various substituted pyrroles were prepared via dehydrogenative coupling of secondary alcohols and amino alcohols, and the N-substituted pyrroles were synthesized via dehydrogenative coupling of aromatic amines with cis-2-butene-1,4-diol and 2-butyne-1,4-diol, respectively. Several control reactions and spectroscopic experiments were performed to characterize the catalysts and establish the reaction mechanism.

SrFeO3-δ: a novel Fe4+ ↔ Fe2+ redox mediated pseudocapacitive electrode in aqueous electrolyte.

Pseudocapacitors offer both high energy and high power, making them suitable for grid-scale electrochemical energy storage to harness renewable energy produced from sun, wind, and tides. To overcome performance degradation in terms of cycling fading and lower specific capacitance values at high charge/discharge rates of electrochemical pseudocapacitors based on transition-metal oxides, perovskite-structured SrFeO3-δ was envisaged as a negative electrode that harnesses the Fe4+/3+ and Fe3+/2+ redox couple to deliver superior performance. SrFeO3-δ offers high specific capacitances of ca. 733 F g-1 at a scan rate of 1 mV s-1 and ca. 743 F g-1 at a current density of 1 A g-1 and demonstrates excellent cyclic stability over 2500 repeated cycles with capacitance retention of >92%, achieving 94% coulombic efficiency. The good cycling stability is attributed to the inherent metallic electrical conductivity of SrFeO3-δ and the fortuitous tendency of the robust cation framework structure to accommodate flexible oxygen content. The surface capacitive and diffusion-controlled contributions for capacitance are about ∼30% and ∼70%, respectively, at peak current and a scan rate equivalent to 1 mV s-1. The higher capacitance and stable performance make SrFeO3-δ an economical and abundant pseudocapacitive electrode.

Blood Pressure Variation with Altitudes in Children: A Cross-Sectional Observational Study from Himalayan Hills.

OBJECTIVES: We aimed to evaluate blood pressure (BP) in Indian children who had similar demographic characteristics but hailed from different altitudes. METHODS: BP of school going children, aged 5 to 12 years, at five different locations varying in altitude (near sea level: n = 425; 2000 feet: n = 244; 4000 feet: n = 248; 6000 feet: n = 242 and 8000 feet: n = 250) was measured in a mountainous district in Himalaya. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were recorded by aneroid sphygmomanometer in the sitting posture using a calibrated instrument and four trained resident doctors. The average of three readings was taken. RESULTS: Of the 1229 children whose data were analyzed, 50.4% were boys. SBP showed a progressive rise from 99.5 (4.00) mmHg [mean (standard deviation)] at near sea level to 106.7 (4.17) mmHg at 8000 feet. Similarly, DBP showed a rise from 60.1 (3.67) mmHg to 66.8 (4.58) mmHg over the same altitude range. Analysis of covariance for BP variation with altitude, with age as covariate, indicated a modest but statistically significant rise in both SBP and DBP with altitude. Higher BP values was noted among children residing at higher than at lower altitude (0.8% at sea level to 18.8% at 8000 feet). Correlations between SBP and DBP values and height and weight, though positive and significant at p < 0.01 level, were weak. CONCLUSIONS: These data will help in correct interpretation of BP readings in children residing at high altitude.

Iron-Catalyzed Metal-Ligand Cooperative Approach toward Sustainable Synthesis of Azines and N-Acylhydrazones in Air.

Herein, we describe a metal-ligand cooperative approach for the sustainable synthesis of various aldazines, ketazines, and N-acylhydrazones via dehydrogenative functionalization of alcohols with hydrazine hydrate using a simple, easy-to-prepare iron catalyst featuring a redox noninnocent tridentate arylazo backbone. Our catalyst is compatible with both primary and secondary alcohols to produce a wide variety of substituted aldazines, ketazines, and N-acylhydrazones in good isolated yields in air. A series of control experiments are performed to elucidate the reaction mechanism.

Ligand centered redox enabled sustainable synthesis of triazines and pyrimidines using a zinc-stabilized azo-anion radical catalyst.

Herein, we report ligand-centered redox controlled Zn(II)-catalyzed multicomponent approaches for synthesizing pyrimidines and triazines. Taking advantage of the ligand-centered redox events and using a well-defined Zn(II)-catalyst (1a) bearing (E)-2-((4-chlorophenyl)diazenyl)-1,10-phenanthroline (L1a) as the redox-active ligand, a wide variety of substituted pyrimidines and triazines were prepared via dehydrogenative alcohol functionalization reactions. Pyrimidines were prepared via two pathways: (i) dehydrogenative coupling of primary and secondary alcohols with amidines and (ii) dehydrogenative coupling of primary alcohols with alkynes and amidines. Triazines were prepared via dehydrogenative coupling of alcohols and amidines. Catalyst 1a is well tolerant to a wide range of substrates yielding the desired pyrimidines and triazines in moderate to good isolated yields. A series of control reactions were performed to predict the plausible mechanism, suggesting that the active participation of the ligand-centered redox events enables the Zn(II)-complex 1a to act as an efficient catalyst for synthesizing these N-heterocycles. Electron transfer processes occur at the azo-aromatic ligand throughout the catalytic reaction, and the Zn(II)-center serves only as a template.

Synthesis, Characterizations, and Electrochemical Performances of Highly Porous, Anhydrous Co0.5Ni0.5C2O4 for Pseudocapacitive Energy Storage Applications.

Electrochemical energy storage relies essentially on the development of innovative electrode materials with enhanced kinetics of ion transport. Pseudocapacitors are excellent candidates to bridge the performance gap between supercapacitors and batteries. Highly porous, anhydrous Ni0.5Co0.5C2O4 is envisaged here as a potential electrode for pseudocapacitor applications, mainly because of its open pore framework structure, which poses inherent structural stability due to the presence of planar oxalate anions (C2O4 2-), and active participation of Ni2+/3+ and Co2+/3+ results in high intercalative charge storage capacity in the aqueous KOH electrolyte. The Ni0.5Co0.5C2O4 electrode shows specific capacitance equivalent to 2396 F/g at 1 A/g in the potential window of 0.6 V in the aqueous 2 M KOH electrolyte by galvanostatic charge/discharge experiments. Predominant pseudocapacitive mechanism seems to operative behind high charge storage due to active participation of Ni2+/3+ and Co2+/3+ redox couple as intercalative (inner) and surface (outer) charges stored by porous anhydrous Co0.5Ni0.5C2O4 were close to high 38 and 62% respectively. Further, in full cell asymmetric supercapacitors (ASCs) in which porous anhydrous Co0.5Ni0.5C2O4 was used as the positive electrode and activated carbon (AC) was utilized as the negative electrode, in the operating potential window 1.6 V, the highest specific energy of 283 W h/kg and specific power of ∼817 W/kg were achieved at 1 A/g current rates. Even at a very high power density of 7981 W/kg, the hybrid supercapacitor still attains an energy density of ∼75 W h/kg with high cyclic stability at a 10 A/g current rate. The detailed electrochemical studies confirm higher cyclic stability and a superior electrochemical energy storage property of porous anhydrous Co0.5Ni0.5C2O4, making it a potential pseudocapacitive electrode for large energy storage applications.

Newborn joint mechanics.

INTRODUCTION: We aimed to evaluate joint mechanics in newborn by goniometric assessment of major joints in healthy babies born at different gestational ages (GAs). MATERIALS AND METHODS: An institution based observational study was carried out on healthy newborn babies within two days of birth. Study subjects were born at 28-41 completed weeks of gestation. The major joints of upper and lower limbs were assessed with manual goniometer for joint angles in relation to specific passive movements and range of motion (ROM) calculated where applicable. All measurements were made by a single observer with careful consideration of plane of movement and axes involved. Strength of association between joint angles and GA was quantified by Pearson's r coefficient. RESULTS: Six major joints (shoulder, elbow, wrist, hip, knee, and ankle) were evaluated on either side in 433 babies. No significant differences were found between male and female babies and left or right side of the body. For most joints, a secular declining trend of joint angle or ROM was noted with good to strong inverse correlation with GA. The strongest associations were for flexion-extension ROM and adduction-abduction ROM at shoulder, palmar flexion at wrist and dorsiflexion at ankle joint with r values of -0.76, -0.75, -0.75, and -0.75, respectively. CONCLUSIONS: The reading of a specific joint angle in the newborn infants was found to be dependent on GA. Precise calibration of gestation appropriate joint angles had laid down the foundation for functional assessment of multimodal joint mechanics.HighlightsEvaluation of newborn joint angles require stringent attention toward the plane and axis of the particular joint movement being assessed.Major joint angles and range of motion in newborn infants were observed to follow a secular declining trend according to the gestational age.Precise estimation of gestation appropriate joint angle will be helpful to understand the mechanics of musculoskeletal medicine in newborn.

Metal-ligand cooperative approaches in homogeneous catalysis using transition metal complex catalysts of redox noninnocent ligands.

Catalysis offers a straightforward route to prepare various value-added molecules starting from readily available raw materials. The catalytic reactions mostly involve multi-electron transformations. Hence, compared to the inexpensive and readily available 3d-metals, the 4d and 5d-transition metals get an extra advantage for performing multi-electron catalytic reactions as the heavier transition metals prefer two-electron redox events. However, for sustainable development, these expensive and scarce heavy metal-based catalysts need to be replaced by inexpensive, environmentally benign, and economically affordable 3d-metal catalysts. In this regard, a metal-ligand cooperative approach involving transition metal complexes of redox noninnocent ligands offers an attractive alternative. The synergistic participation of redox-active ligands during electron transfer events allows multi-electron transformations using 3d-metal catalysts and allows interesting chemical transformations using 4d and 5d-metals as well. Herein we summarize an up-to-date literature report on the metal-ligand cooperative approaches using transition metal complexes of redox noninnocent ligands as catalysts for a few selected types of catalytic reactions.

La1-x K x FeO3-δ: An Anion Intercalative Pseudocapacitive Electrode for Supercapacitor Application.

The green energy alternative to a fossil fuel-based economy can be provided only by coupling renewable energy solution solutions such as solar or wind energy plants with large-scale electrochemical energy storage devices. Enabling high-energy storage coupled with high-power delivery can be envisaged though high-capacitive pseudocapacitor electrodes. A pseudocapacitor electrode with multiple oxidation state accessibility can enable more than 1e - charge/transfer per molecule to facilitate superior energy storage. K-doped LaFeO3 (La1-x K x FeO3-δ) is presented here as an electrode having a high pseudocapacitance storage, equivalent to 1.32e - charge/transfer per molecule, resulting in a capacity equivalent of 662 F/g at 1 mV/s scan rate by introduction of a layered potential over the Fe-ion octahedral to utilize higher redox state energies (Fe4+→ Fe2+). La/K ordering in orthorhombic perovskite (La1-x K x FeO3-δ) made the Fe4+ oxidation state accessible, and a systematic shift in the redox energies of Fe4+/3+ and Fe3+/2+ redox couples was observed with K+ ion doping in the A site of the LaFeO3 perovskite, which resulted in a high faradic contribution to the capacitance, coupled with anionic intercalation of H2O/OH- in the host perovskite lattice. The surface capacitive and diffusion control contributions for capacitance are about 42 and 58%, respectively, at -0.6 V, with a scan rate of 1  mV/s. A high gravimetric capacitance, equivalent to 619, 347, 188, 121, and 65 F/g, respectively, at 1, 2, 3, 5, and 10 A/g constant current, was observed for the La0.5K0.5FeO3-δ electrode. Up to 88.9% capacitive retention and 97% Coulombic efficacy were obtained for continuous 5000 cycles of charge/discharge for the La0.5K0.5FeO3-δ electrode. The gravimetric capacitance values of ASCs (activated carbon//La0.5K0.5FeO3-δ) are 348, 290, 228, and 147 F/g at current densities of 1, 2, 3, and 5 A/g, respectively. A maximum specific power of ∼3594 W/kg was obtained when the specific energy reached ∼117 Wh/kg at 5 A/g of current density.

Nickel catalyzed sustainable synthesis of benzazoles and purines via acceptorless dehydrogenative coupling and borrowing hydrogen approach.

Herein we report nickel-catalyzed sustainable synthesis of a few chosen five-membered fused nitrogen heterocycles such as benzimidazole, purine, benzothiazole, and benzoxazole via acceptorless dehydrogenative functionalization of alcohols. Using a bench stable, easy to prepare, and inexpensive Ni(ii)-catalyst, [Ni(MeTAA)] (1a), featuring a tetraaza macrocyclic ligand (tetramethyltetraaza[14]annulene (MeTAA)), a wide variety of polysubstituted benzimidazole, purine, benzothiazole, and benzoxazole derivatives were prepared via dehydrogenative coupling of alcohols with 1,2-diaminobenzene, 4,5-diaminopyrimidine, 2-aminothiphenol, and 2-aminophenol, respectively. A wide array of benzimidazoles were also prepared via a borrowing hydrogen approach involving alcohols as hydrogen donors and 2-nitroanilines as hydrogen acceptors. A few control experiments were performed to understand the reaction mechanism.

COVID-19 and Co-infection in Children: The Indian Perspectives.

BACKGROUND AND OBJECTIVES: Assessing the co-infections with COVID-19 is crucial to delineate its true clinical impact. Pediatric information in this aspect is limited. Our study aims to analyze the spectrum of co-infections in pediatric COVID-19 patients and determine the clinical as well as laboratory parameters predicting co-infection. METHODOLOGY: In this prospective observational study conducted from June to December 2020 in a single tertiary care institution, data pertaining to demographic, illness and treatment-related variables were analyzed among two subsets of pediatric patients of age 1 month-12 years with RT-PCR-confirmed COVID-19 infection-Group A: those with confirmed co-infection and Group B: moderate to severe disease without co-infection. Among Group A, etiology of co-infection was characterized through relevant microbiological examination within 48 h admission. RESULT: Among our study population, 15.03% and 20.6% had co-infections and moderate to severe disease respectively. Among those with confirmed co-infection, 32.5%, 11.6% and 6.97% recorded blood culture, respiratory secretion and CSF growth, respectively, the picture being dominated by Methicillin resistant and sensitive Staphylococcus aureus. Serum serology demonstrated Scrub typhus infection to be most prevalent. Concurrent respiratory viral infections were seen in 11.6%. Children with co-infection had significantly higher morbidity and need for supportive therapy. Predictors of co-infection were localization of infection, Neutrophil count ≥10×109, age-specific lymphopenia, CRP > 100 mg/dl and hyperferritinemia. CONCLUSION: Co-infections are an important factor prognosticating pediatric COVID infection. Their early detection, prompt and appropriate treatment is of paramount importance.

Iron-Catalyzed Alkyne-Based Multicomponent Synthesis of Pyrimidines under Air.

An iron-catalyzed sustainable, economically affordable, and eco-friendly synthetic protocol for the construction of various trisubstituted pyrimidines is described. A wide range of trisubstituted pyrimidines were prepared using a well-defined, easy to prepare, bench-stable, and phosphine-free iron catalyst featuring a redox-noninnocent tridentate arylazo pincer under comparatively mild aerobic conditions via dehydrogenative functionalization of alcohols with alkynes and amidines.